This perhaps ridiculous-seeming module was created to test routines
that manipulate random numbers by providing a known output from
rand.  Given a list of seeds with srand, it will return each in
turn.  After seeded random numbers are exhausted, it will always
return 0.  Seed numbers must be of a form that meets the expected
output from rand as called with no arguments -- i.e.  they must be
between 0 (inclusive) and 1 (exclusive).  In order to facilitate
generating and testing a nearly-one number, this module exports the
function oneish, which returns a number just fractionally less than
one.
